ESB-2026.4667

=========================================================================== AUSCERT External Security Bulletin Redistribution ESB-2026.4667 USN-8233-1: nghttp2 vulnerability 6 May 2026 =========================================================================== AUSCERT Security Bulletin Summary --------------------------------- Product: nghttp2 Publisher: Ubuntu Operating System: Ubuntu Resolution: Patch/Upgrade CVE Names: CVE-2026-27135 Original Bulletin: https://ubuntu.com/security/notices/USN-8233-1 Comment: CVSS (Max): 7.5 CVE-2026-27135 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H) CVSS Source: Ubuntu Calculator: https://www.first.org/cvss/calculator/3.1#CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H EPSS (Max): 0.0% (6th) CVE-2026-27135 2026-05-05 - --------------------------BEGIN INCLUDED TEXT-------------------- USN-8233-1: nghttp2 vulnerability Publication date 5 May 2026 Overview nghttp2 could be made to crash if it received specially crafted network traffic. Releases 25.10 24.04 LTS 22.04 LTS 20.04 LTS 18.04 LTS 16.04 --------------------------------------------------------------------------------- Open side navigation Packages o nghttp2 - HTTP/2 C Library and tools Details Andrew MacPherson discovered that nghttp2 did not properly validate internal state when the session termination API was called. A remote attacker could possibly use this issue to cause nghttp2 to crash, resulting in a denial of service. Update instructions The problem can be corrected by updating your system to the following package versions: Ubuntu Package Version Release 25.10 libnghttp2-14 - 1.64.0-1.1ubuntu1.1 questing nghttp2 - 1.64.0-1.1ubuntu1.1 24.04 libnghttp2-14 - 1.59.0-1ubuntu0.3 LTS noble nghttp2 - 1.59.0-1ubuntu0.3 22.04 libnghttp2-14 - 1.43.0-1ubuntu0.3 LTS jammy nghttp2 - 1.43.0-1ubuntu0.3 20.04 libnghttp2-14 - 1.40.0-1ubuntu0.3+esm1 Ubuntu Pro Fix available with LTS Ubuntu Pro . focal nghttp2 - 1.40.0-1ubuntu0.3+esm1 Ubuntu Pro Fix available with Ubuntu Pro . 18.04 libnghttp2-14 - 1.30.0-1ubuntu1+esm3 Ubuntu Pro Fix available with LTS Ubuntu Pro . bionic nghttp2 - 1.30.0-1ubuntu1+esm3 Ubuntu Pro Fix available with Ubuntu Pro . libnghttp2-14 - 1.7.1-1ubuntu0.1~esm3 Ubuntu Pro Fix available with Ubuntu Pro via ESM Apps. A community fix might become publicly 16.04 available in the future. xenial nghttp2 - 1.7.1-1ubuntu0.1~esm3 Ubuntu Pro Fix available with Ubuntu Pro via ESM Apps. A community fix might become publicly available in the future. --------------------------------------------------------------------------------- References o CVE-2026-27135 - --------------------------END INCLUDED TEXT---------------------- You have received this e-mail bulletin as a result of your organisation's registration with AUSCERT. The mailing list you are subscribed to is maintained within your organisation, so if you do not wish to continue receiving these bulletins you should contact your local IT manager. If you do not know who that is, please send an email to auscert@auscert.org.au and we will forward your request to the appropriate person. NOTE: Third Party Rights This security bulletin is provided as a service to AUSCERT's members. As AUSCERT did not write the document quoted above, AUSCERT has had no control over its content. The decision to follow or act on information or advice contained in this security bulletin is the responsibility of each user or organisation, and should be considered in accordance with your organisation's site policies and procedures. AUSCERT takes no responsibility for consequences which may arise from following or acting on information or advice contained in this security bulletin. NOTE: This is only the original release of the security bulletin. It may not be updated when updates to the original are made. If downloading at a later date, it is recommended that the bulletin is retrieved directly from the author's website to ensure that the information is still current. Contact information for the authors of the original document is included in the Security Bulletin above. If you have any questions or need further information, please contact them directly. Previous advisories and external security bulletins can be retrieved from: https://portal.auscert.org.au/bulletins/ =========================================================================== AUSCERT The University of Queensland, Brisbane QLD 4072 Australia e: auscert@auscert.org.au t: +61 (0)7 3365 4417 Allies in Cyber Security ===========================================================================